ui: Create the gfx::QuadF class.

ui/gfx/quad_f.h

Index: ui/gfx/quad_f.h
diff --git a/ui/gfx/quad_f.h b/ui/gfx/quad_f.h
new file mode 100644
index 0000000000000000000000000000000000000000..7e6bce10579c10ddf889efd102447f95f7303e26
--- /dev/null
+++ b/ui/gfx/quad_f.h
@@ -0,0 +1,94 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef UI_GFX_QUAD_F_H_
+#define UI_GFX_QUAD_F_H_
+
+#include <string>
+
+#include "ui/base/ui_export.h"
+#include "ui/gfx/point_f.h"
+#include "ui/gfx/rect_f.h"
+
+namespace gfx {
+
+// A Quad is defined by four corners, allowing it to have edges that are not
+// axis-aligned, unlike a Rect.
+class UI_EXPORT QuadF {
+ public:
+  QuadF();
+  QuadF(const PointF& p1, const PointF& p2, const PointF& p3, const PointF& p4);
+  explicit QuadF(const RectF& rect);
+  ~QuadF();
+
+  void operator=(const QuadF& quad);
+  void operator=(const RectF& rect);
+
+  void set_p1(const PointF& p) { p1_ = p; }
+  void set_p2(const PointF& p) { p2_ = p; }
+  void set_p3(const PointF& p) { p3_ = p; }
+  void set_p4(const PointF& p) { p4_ = p; }
+
+  const PointF& p1() const { return p1_; }
+  const PointF& p2() const { return p2_; }
+  const PointF& p3() const { return p3_; }
+  const PointF& p4() const { return p4_; }
+
+  // Returns true if the quad is an axis-aligned rectangle.
+  bool IsRectilinear() const;
+
+  // Returns true if the points of the quad are in counter-clockwise order. This
+  // assumes that the quad is convex, and that no three points are collinear.
+  bool IsCounterClockwise() const;
+
+  // Returns true if the |point| is contained within the quad, or lies on on
+  // edge of the quad.
+  bool Contains(const gfx::PointF& point) const;
+
+  // Returns a rectangle that bounds the four points of the quad. The points of
+  // the quad may lie on the right/bottom edge of the resulting rectangle,
+  // rather than being strictly inside it.
+  RectF BoundingBox() const;
+
+  // Add a vector to the quad, offseting each point in the quad by the vector.
+  void operator+=(const Vector2dF& rhs);
+  // Subtract a vector from the quad, offseting each point in the quad by the
+  // inverse of the vector.
+  void operator-=(const Vector2dF& rhs);
+
+  // Scale each point in the quad by the |scale| factor.
+  void Scale(float scale) { Scale(scale, scale); }
+
+  // Scale each point in the quad by the scale factors along each axis.
+  void Scale(float x_scale, float y_scale);
+
+  // Returns a string representation of quad.
+  std::string ToString() const;
+
+ private:
+  PointF p1_;
+  PointF p2_;
+  PointF p3_;
+  PointF p4_;
+};
+
+inline bool operator==(const QuadF& lhs, const QuadF& rhs) {
+  return
+      lhs.p1() == rhs.p1() && lhs.p2() == rhs.p2() &&

[tfarina, 2012/11/02 15:59:10]

nit: it fits in the previous line, you don't need to wrap and indent 4 spaces.

+      lhs.p3() == rhs.p3() && lhs.p4() == rhs.p4();
+}
+
+inline bool operator!=(const QuadF& lhs, const QuadF& rhs) {
+  return !(lhs == rhs);
+}
+
+// Add a vector to a quad, offseting each point in the quad by the vector.
+UI_EXPORT QuadF operator+(const QuadF& lhs, const Vector2dF& rhs);
+// Subtract a vector from a quad, offseting each point in the quad by the
+// inverse of the vector.
+UI_EXPORT QuadF operator-(const QuadF& lhs, const Vector2dF& rhs);
+
+}  // namespace gfx
+
+#endif  // UI_GFX_QUAD_F_H_